summaryrefslogtreecommitdiffstats
path: root/net/sunrpc/xprtrdma/svc_rdma_transport.c
blob: 3fe665152d954a650cd01751cabbe548a0a24d0e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/*
 * Copyright (c) 2015-2018 Oracle. All rights reserved.
 * Copyright (c) 2014 Open Grid Computing, Inc. All rights reserved.
 * Copyright (c) 2005-2007 Network Appliance, Inc. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the BSD-type
 * license below:
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *      Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *      Redistributions in binary form must reproduce the above
 *      copyright notice, this list of conditions and the following
 *      disclaimer in the documentation and/or other materials provided
 *      with the distribution.
 *
 *      Neither the name of the Network Appliance, Inc. nor the names of
 *      its contributors may be used to endorse or promote products
 *      derived from this software without specific prior written
 *      permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Author: Tom Tucker <tom@opengridcomputing.com>
 */

#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/export.h>

#include <rdma/ib_verbs.h>
#include <rdma/rdma_cm.h>
#include <rdma/rw.h>

#include <linux/sunrpc/addr.h>
#include <linux/sunrpc/debug.h>
#include <linux/sunrpc/rpc_rdma.h>
#include <linux/sunrpc/svc_xprt.h>
#include <linux/sunrpc/svc_rdma.h>

#include "xprt_rdma.h"
#include <trace/events/rpcrdma.h>

#define RPCDBG_FACILITY	RPCDBG_SVCXPRT

static struct svcxprt_rdma *svc_rdma_create_xprt(struct svc_serv *serv,
						 struct net *net);
static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
					struct net *net,
					struct sockaddr *sa, int salen,
					int flags);
static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt);
static void svc_rdma_release_rqst(struct svc_rqst *);
static void svc_rdma_detach(struct svc_xprt *xprt);
static void svc_rdma_free(struct svc_xprt *xprt);
static int svc_rdma_has_wspace(struct svc_xprt *xprt);
static void svc_rdma_secure_port(struct svc_rqst *);
static void svc_rdma_kill_temp_xprt(struct svc_xprt *);

static const struct svc_xprt_ops svc_rdma_ops = {
	.xpo_create = svc_rdma_create,
	.xpo_recvfrom = svc_rdma_recvfrom,
	.xpo_sendto = svc_rdma_sendto,
	.xpo_release_rqst = svc_rdma_release_rqst,
	.xpo_detach = svc_rdma_detach,
	.xpo_free = svc_rdma_free,
	.xpo_has_wspace = svc_rdma_has_wspace,
	.xpo_accept = svc_rdma_accept,
	.xpo_secure_port = svc_rdma_secure_port,
	.xpo_kill_temp_xprt = svc_rdma_kill_temp_xprt,
};

struct svc_xprt_class svc_rdma_class = {
	.xcl_name = "rdma",
	.xcl_owner = THIS_MODULE,
	.xcl_ops = &svc_rdma_ops,
	.xcl_max_payload = RPCSVC_MAXPAYLOAD_RDMA,
	.xcl_ident = XPRT_TRANSPORT_RDMA,
};

/* QP event handler */
static void qp_event_handler(struct ib_event *event, void *context)
{
	struct svc_xprt *xprt = context;

	trace_svcrdma_qp_error(event, (struct sockaddr *)&xprt->xpt_remote);
	switch (event->event) {
	/* These are considered benign events */
	case IB_EVENT_PATH_MIG:
	case IB_EVENT_COMM_EST:
	case IB_EVENT_SQ_DRAINED:
	case IB_EVENT_QP_LAST_WQE_REACHED:
		break;

	/* These are considered fatal events */
	case IB_EVENT_PATH_MIG_ERR:
	case IB_EVENT_QP_FATAL:
	case IB_EVENT_QP_REQ_ERR:
	case IB_EVENT_QP_ACCESS_ERR:
	case IB_EVENT_DEVICE_FATAL:
	default:
		set_bit(XPT_CLOSE, &xprt->xpt_flags);
		svc_xprt_enqueue(xprt);
		break;
	}
}

static struct svcxprt_rdma *svc_rdma_create_xprt(struct svc_serv *serv,
						 struct net *net)
{
	struct svcxprt_rdma *cma_xprt = kzalloc(sizeof *cma_xprt, GFP_KERNEL);

	if (!cma_xprt) {
		dprintk("svcrdma: failed to create new transport\n");
		return NULL;
	}
	svc_xprt_init(net, &svc_rdma_class, &cma_xprt->sc_xprt, serv);
	INIT_LIST_HEAD(&cma_xprt->sc_accept_q);
	INIT_LIST_HEAD(&cma_xprt->sc_rq_dto_q);
	INIT_LIST_HEAD(&cma_xprt->sc_read_complete_q);
	INIT_LIST_HEAD(&cma_xprt->sc_send_ctxts);
	INIT_LIST_HEAD(&cma_xprt->sc_recv_ctxts);
	INIT_LIST_HEAD(&cma_xprt->sc_rw_ctxts);
	init_waitqueue_head(&cma_xprt->sc_send_wait);

	spin_lock_init(&cma_xprt->sc_lock);
	spin_lock_init(&cma_xprt->sc_rq_dto_lock);
	spin_lock_init(&cma_xprt->sc_send_lock);
	spin_lock_init(&cma_xprt->sc_recv_lock);
	spin_lock_init(&cma_xprt->sc_rw_ctxt_lock);

	/*
	 * Note that this implies that the underlying transport support
	 * has some form of congestion control (see RFC 7530 section 3.1
	 * paragraph 2). For now, we assume that all supported RDMA
	 * transports are suitable here.
	 */
	set_bit(XPT_CONG_CTRL, &cma_xprt->sc_xprt.xpt_flags);

	return cma_xprt;
}

static void
svc_rdma_parse_connect_private(struct svcxprt_rdma *newxprt,
			       struct rdma_conn_param *param)
{
	const struct rpcrdma_connect_private *pmsg = param->private_data;

	if (pmsg &&
	    pmsg->cp_magic == rpcrdma_cmp_magic &&
	    pmsg->cp_version == RPCRDMA_CMP_VERSION) {
		newxprt->sc_snd_w_inv = pmsg->cp_flags &
					RPCRDMA_CMP_F_SND_W_INV_OK;

		dprintk("svcrdma: client send_size %u, recv_size %u "
			"remote inv %ssupported\n",
			rpcrdma_decode_buffer_size(pmsg->cp_send_size),
			rpcrdma_decode_buffer_size(pmsg->cp_recv_size),
			newxprt->sc_snd_w_inv ? "" : "un");
	}
}

/*
 * This function handles the CONNECT_REQUEST event on a listening
 * endpoint. It is passed the cma_id for the _new_ connection. The context in
 * this cma_id is inherited from the listening cma_id and is the svc_xprt
 * structure for the listening endpoint.
 *
 * This function creates a new xprt for the new connection and enqueues it on
 * the accept queue for the listent xprt. When the listen thread is kicked, it
 * will call the recvfrom method on the listen xprt which will accept the new
 * connection.
 */
static void handle_connect_req(struct rdma_cm_id *new_cma_id,
			       struct rdma_conn_param *param)
{
	struct svcxprt_rdma *listen_xprt = new_cma_id->context;
	struct svcxprt_rdma *newxprt;
	struct sockaddr *sa;

	/* Create a new transport */
	newxprt = svc_rdma_create_xprt(listen_xprt->sc_xprt.xpt_server,
				       listen_xprt->sc_xprt.xpt_net);
	if (!newxprt)
		return;
	newxprt->sc_cm_id = new_cma_id;
	new_cma_id->context = newxprt;
	svc_rdma_parse_connect_private(newxprt, param);

	/* Save client advertised inbound read limit for use later in accept. */
	newxprt->sc_ord = param->initiator_depth;

	sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.dst_addr;
	svc_xprt_set_remote(&newxprt->sc_xprt, sa, svc_addr_len(sa));
	/* The remote port is arbitrary and not under the control of the
	 * client ULP. Set it to a fixed value so that the DRC continues
	 * to be effective after a reconnect.
	 */
	rpc_set_port((struct sockaddr *)&newxprt->sc_xprt.xpt_remote, 0);

	sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.src_addr;
	svc_xprt_set_local(&newxprt->sc_xprt, sa, svc_addr_len(sa));

	/*
	 * Enqueue the new transport on the accept queue of the listening
	 * transport
	 */
	spin_lock(&listen_xprt->sc_lock);
	list_add_tail(&newxprt->sc_accept_q, &listen_xprt->sc_accept_q);
	spin_unlock(&listen_xprt->sc_lock);

	set_bit(XPT_CONN, &listen_xprt->sc_xprt.xpt_flags);
	svc_xprt_enqueue(&listen_xprt->sc_xprt);
}

/*
 * Handles events generated on the listening endpoint. These events will be
 * either be incoming connect requests or adapter removal  events.
 */
static int rdma_listen_handler(struct rdma_cm_id *cma_id,
			       struct rdma_cm_event *event)
{
	struct sockaddr *sap = (struct sockaddr *)&cma_id->route.addr.src_addr;

	trace_svcrdma_cm_event(event, sap);

	switch (event->event) {
	case RDMA_CM_EVENT_CONNECT_REQUEST:
		dprintk("svcrdma: Connect request on cma_id=%p, xprt = %p, "
			"event = %s (%d)\n", cma_id, cma_id->context,
			rdma_event_msg(event->event), event->event);
		handle_connect_req(cma_id, &event->param.conn);
		break;
	default:
		/* NB: No device removal upcall for INADDR_ANY listeners */
		dprintk("svcrdma: Unexpected event on listening endpoint %p, "
			"event = %s (%d)\n", cma_id,
			rdma_event_msg(event->event), event->event);
		break;
	}

	return 0;
}

static int rdma_cma_handler(struct rdma_cm_id *cma_id,
			    struct rdma_cm_event *event)
{
	struct sockaddr *sap = (struct sockaddr *)&cma_id->route.addr.dst_addr;
	struct svcxprt_rdma *rdma = cma_id->context;
	struct svc_xprt *xprt = &rdma->sc_xprt;

	trace_svcrdma_cm_event(event, sap);

	switch (event->event) {
	case RDMA_CM_EVENT_ESTABLISHED:
		/* Accept complete */
		svc_xprt_get(xprt);
		dprintk("svcrdma: Connection completed on DTO xprt=%p, "
			"cm_id=%p\n", xprt, cma_id);
		clear_bit(RDMAXPRT_CONN_PENDING, &rdma->sc_flags);
		svc_xprt_enqueue(xprt);
		break;
	case RDMA_CM_EVENT_DISCONNECTED:
		dprintk("svcrdma: Disconnect on DTO xprt=%p, cm_id=%p\n",
			xprt, cma_id);
		set_bit(XPT_CLOSE, &xprt->xpt_flags);
		svc_xprt_enqueue(xprt);
		svc_xprt_put(xprt);
		break;
	case RDMA_CM_EVENT_DEVICE_REMOVAL:
		dprintk("svcrdma: Device removal cma_id=%p, xprt = %p, "
			"event = %s (%d)\n", cma_id, xprt,
			rdma_event_msg(event->event), event->event);
		set_bit(XPT_CLOSE, &xprt->xpt_flags);
		svc_xprt_enqueue(xprt);
		svc_xprt_put(xprt);
		break;
	default:
		dprintk("svcrdma: Unexpected event on DTO endpoint %p, "
			"event = %s (%d)\n", cma_id,
			rdma_event_msg(event->event), event->event);
		break;
	}
	return 0;
}

/*
 * Create a listening RDMA service endpoint.
 */
static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
					struct net *net,
					struct sockaddr *sa, int salen,
					int flags)
{
	struct rdma_cm_id *listen_id;
	struct svcxprt_rdma *cma_xprt;
	int ret;

	dprintk("svcrdma: Creating RDMA listener\n");
	if ((sa->sa_family != AF_INET) && (sa->sa_family != AF_INET6)) {
		dprintk("svcrdma: Address family %d is not supported.\n", sa->sa_family);
		return ERR_PTR(-EAFNOSUPPORT);
	}
	cma_xprt = svc_rdma_create_xprt(serv, net);
	if (!cma_xprt)
		return ERR_PTR(-ENOMEM);
	set_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags);
	strcpy(cma_xprt->sc_xprt.xpt_remotebuf, "listener");

	listen_id = rdma_create_id(net, rdma_listen_handler, cma_xprt,
				   RDMA_PS_TCP, IB_QPT_RC);
	if (IS_ERR(listen_id)) {
		ret = PTR_ERR(listen_id);
		dprintk("svcrdma: rdma_create_id failed = %d\n", ret);
		goto err0;
	}

	/* Allow both IPv4 and IPv6 sockets to bind a single port
	 * at the same time.
	 */
#if IS_ENABLED(CONFIG_IPV6)
	ret = rdma_set_afonly(listen_id, 1);
	if (ret) {
		dprintk("svcrdma: rdma_set_afonly failed = %d\n", ret);
		goto err1;
	}
#endif
	ret = rdma_bind_addr(listen_id, sa);
	if (ret) {
		dprintk("svcrdma: rdma_bind_addr failed = %d\n", ret);
		goto err1;
	}
	cma_xprt->sc_cm_id = listen_id;

	ret = rdma_listen(listen_id, RPCRDMA_LISTEN_BACKLOG);
	if (ret) {
		dprintk("svcrdma: rdma_listen failed = %d\n", ret);
		goto err1;
	}

	/*
	 * We need to use the address from the cm_id in case the
	 * caller specified 0 for the port number.
	 */
	sa = (struct sockaddr *)&cma_xprt->sc_cm_id->route.addr.src_addr;
	svc_xprt_set_local(&cma_xprt->sc_xprt, sa, salen);

	return &cma_xprt->sc_xprt;

 err1:
	rdma_destroy_id(listen_id);
 err0:
	kfree(cma_xprt);
	return ERR_PTR(ret);
}

/*
 * This is the xpo_recvfrom function for listening endpoints. Its
 * purpose is to accept incoming connections. The CMA callback handler
 * has already created a new transport and attached it to the new CMA
 * ID.
 *
 * There is a queue of pending connections hung on the listening
 * transport. This queue contains the new svc_xprt structure. This
 * function takes svc_xprt structures off the accept_q and completes
 * the connection.
 */
static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt)
{
	struct svcxprt_rdma *listen_rdma;
	struct svcxprt_rdma *newxprt = NULL;
	struct rdma_conn_param conn_param;
	struct rpcrdma_connect_private pmsg;
	struct ib_qp_init_attr qp_attr;
	unsigned int ctxts, rq_depth;
	struct ib_device *dev;
	int ret = 0;
	RPC_IFDEBUG(struct sockaddr *sap);

	listen_rdma = container_of(xprt, struct svcxprt_rdma, sc_xprt);
	clear_bit(XPT_CONN, &xprt->xpt_flags);
	/* Get the next entry off the accept list */
	spin_lock(&listen_rdma->sc_lock);
	if (!list_empty(&listen_rdma->sc_accept_q)) {
		newxprt = list_entry(listen_rdma->sc_accept_q.next,
				     struct svcxprt_rdma, sc_accept_q);
		list_del_init(&newxprt->sc_accept_q);
	}
	if (!list_empty(&listen_rdma->sc_accept_q))
		set_bit(XPT_CONN, &listen_rdma->sc_xprt.xpt_flags);
	spin_unlock(&listen_rdma->sc_lock);
	if (!newxprt)
		return NULL;

	dprintk("svcrdma: newxprt from accept queue = %p, cm_id=%p\n",
		newxprt, newxprt->sc_cm_id);

	dev = newxprt->sc_cm_id->device;
	newxprt->sc_port_num = newxprt->sc_cm_id->port_num;

	/* Qualify the transport resource defaults with the
	 * capabilities of this particular device */
	/* Transport header, head iovec, tail iovec */
	newxprt->sc_max_send_sges = 3;
	/* Add one SGE per page list entry */
	newxprt->sc_max_send_sges += (svcrdma_max_req_size / PAGE_SIZE) + 1;
	if (newxprt->sc_max_send_sges > dev->attrs.max_send_sge)
		newxprt->sc_max_send_sges = dev->attrs.max_send_sge;
	newxprt->sc_max_req_size = svcrdma_max_req_size;
	newxprt->sc_max_requests = svcrdma_max_requests;
	newxprt->sc_max_bc_requests = svcrdma_max_bc_requests;
	rq_depth = newxprt->sc_max_requests + newxprt->sc_max_bc_requests;
	if (rq_depth > dev->attrs.max_qp_wr) {
		pr_warn("svcrdma: reducing receive depth to %d\n",
			dev->attrs.max_qp_wr);
		rq_depth = dev->attrs.max_qp_wr;
		newxprt->sc_max_requests = rq_depth - 2;
		newxprt->sc_max_bc_requests = 2;
	}
	newxprt->sc_fc_credits = cpu_to_be32(newxprt->sc_max_requests);
	ctxts = rdma_rw_mr_factor(dev, newxprt->sc_port_num, RPCSVC_MAXPAGES);
	ctxts *= newxprt->sc_max_requests;
	newxprt->sc_sq_depth = rq_depth + ctxts;
	if (newxprt->sc_sq_depth > dev->attrs.max_qp_wr) {
		pr_warn("svcrdma: reducing send depth to %d\n",
			dev->attrs.max_qp_wr);
		newxprt->sc_sq_depth = dev->attrs.max_qp_wr;
	}
	atomic_set(&newxprt->sc_sq_avail, newxprt->sc_sq_depth);

	newxprt->sc_pd = ib_alloc_pd(dev, 0);
	if (IS_ERR(newxprt->sc_pd)) {
		dprintk("svcrdma: error creating PD for connect request\n");
		goto errout;
	}
	newxprt->sc_sq_cq = ib_alloc_cq(dev, newxprt, newxprt->sc_sq_depth,
					0, IB_POLL_WORKQUEUE);
	if (IS_ERR(newxprt->sc_sq_cq)) {
		dprintk("svcrdma: error creating SQ CQ for connect request\n");
		goto errout;
	}
	newxprt->sc_rq_cq = ib_alloc_cq(dev, newxprt, rq_depth,
					0, IB_POLL_WORKQUEUE);
	if (IS_ERR(newxprt->sc_rq_cq)) {
		dprintk("svcrdma: error creating RQ CQ for connect request\n");
		goto errout;
	}

	memset(&qp_attr, 0, sizeof qp_attr);
	qp_attr.event_handler = qp_event_handler;
	qp_attr.qp_context = &newxprt->sc_xprt;
	qp_attr.port_num = newxprt->sc_port_num;
	qp_attr.cap.max_rdma_ctxs = ctxts;
	qp_attr.cap.max_send_wr = newxprt->sc_sq_depth - ctxts;
	qp_attr.cap.max_recv_wr = rq_depth;
	qp_attr.cap.max_send_sge = newxprt->sc_max_send_sges;
	qp_attr.cap.max_recv_sge = 1;
	qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
	qp_attr.qp_type = IB_QPT_RC;
	qp_attr.send_cq = newxprt->sc_sq_cq;
	qp_attr.recv_cq = newxprt->sc_rq_cq;
	dprintk("svcrdma: newxprt->sc_cm_id=%p, newxprt->sc_pd=%p\n",
		newxprt->sc_cm_id, newxprt->sc_pd);
	dprintk("    cap.max_send_wr = %d, cap.max_recv_wr = %d\n",
		qp_attr.cap.max_send_wr, qp_attr.cap.max_recv_wr);
	dprintk("    cap.max_send_sge = %d, cap.max_recv_sge = %d\n",
		qp_attr.cap.max_send_sge, qp_attr.cap.max_recv_sge);

	ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd, &qp_attr);
	if (ret) {
		dprintk("svcrdma: failed to create QP, ret=%d\n", ret);
		goto errout;
	}
	newxprt->sc_qp = newxprt->sc_cm_id->qp;

	if (!(dev->attrs.device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS))
		newxprt->sc_snd_w_inv = false;
	if (!rdma_protocol_iwarp(dev, newxprt->sc_port_num) &&
	    !rdma_ib_or_roce(dev, newxprt->sc_port_num))
		goto errout;

	if (!svc_rdma_post_recvs(newxprt))
		goto errout;

	/* Swap out the handler */
	newxprt->sc_cm_id->event_handler = rdma_cma_handler;

	/* Construct RDMA-CM private message */
	pmsg.cp_magic = rpcrdma_cmp_magic;
	pmsg.cp_version = RPCRDMA_CMP_VERSION;
	pmsg.cp_flags = 0;
	pmsg.cp_send_size = pmsg.cp_recv_size =
		rpcrdma_encode_buffer_size(newxprt->sc_max_req_size);

	/* Accept Connection */
	set_bit(RDMAXPRT_CONN_PENDING, &newxprt->sc_flags);
	memset(&conn_param, 0, sizeof conn_param);
	conn_param.responder_resources = 0;
	conn_param.initiator_depth = min_t(int, newxprt->sc_ord,
					   dev->attrs.max_qp_init_rd_atom);
	if (!conn_param.initiator_depth) {
		dprintk("svcrdma: invalid ORD setting\n");
		ret = -EINVAL;
		goto errout;
	}
	conn_param.private_data = &pmsg;
	conn_param.private_data_len = sizeof(pmsg);
	ret = rdma_accept(newxprt->sc_cm_id, &conn_param);
	if (ret)
		goto errout;

#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
	dprintk("svcrdma: new connection %p accepted:\n", newxprt);
	sap = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.src_addr;
	dprintk("    local address   : %pIS:%u\n", sap, rpc_get_port(sap));
	sap = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.dst_addr;
	dprintk("    remote address  : %pIS:%u\n", sap, rpc_get_port(sap));
	dprintk("    max_sge         : %d\n", newxprt->sc_max_send_sges);
	dprintk("    sq_depth        : %d\n", newxprt->sc_sq_depth);
	dprintk("    rdma_rw_ctxs    : %d\n", ctxts);
	dprintk("    max_requests    : %d\n", newxprt->sc_max_requests);
	dprintk("    ord             : %d\n", conn_param.initiator_depth);
#endif

	trace_svcrdma_xprt_accept(&newxprt->sc_xprt);
	return &newxprt->sc_xprt;

 errout:
	dprintk("svcrdma: failure accepting new connection rc=%d.\n", ret);
	trace_svcrdma_xprt_fail(&newxprt->sc_xprt);
	/* Take a reference in case the DTO handler runs */
	svc_xprt_get(&newxprt->sc_xprt);
	if (newxprt->sc_qp && !IS_ERR(newxprt->sc_qp))
		ib_destroy_qp(newxprt->sc_qp);
	rdma_destroy_id(newxprt->sc_cm_id);
	/* This call to put will destroy the transport */
	svc_xprt_put(&newxprt->sc_xprt);
	return NULL;
}

static void svc_rdma_release_rqst(struct svc_rqst *rqstp)
{
}

/*
 * When connected, an svc_xprt has at least two references:
 *
 * - A reference held by the cm_id between the ESTABLISHED and
 *   DISCONNECTED events. If the remote peer disconnected first, this
 *   reference could be gone.
 *
 * - A reference held by the svc_recv code that called this function
 *   as part of close processing.
 *
 * At a minimum one references should still be held.
 */
static void svc_rdma_detach(struct svc_xprt *xprt)
{
	struct svcxprt_rdma *rdma =
		container_of(xprt, struct svcxprt_rdma, sc_xprt);

	/* Disconnect and flush posted WQE */
	rdma_disconnect(rdma->sc_cm_id);
}

static void __svc_rdma_free(struct work_struct *work)
{
	struct svcxprt_rdma *rdma =
		container_of(work, struct svcxprt_rdma, sc_work);
	struct svc_xprt *xprt = &rdma->sc_xprt;

	trace_svcrdma_xprt_free(xprt);

	if (rdma->sc_qp && !IS_ERR(rdma->sc_qp))
		ib_drain_qp(rdma->sc_qp);

	svc_rdma_flush_recv_queues(rdma);

	/* Final put of backchannel client transport */
	if (xprt->xpt_bc_xprt) {
		xprt_put(xprt->xpt_bc_xprt);
		xprt->xpt_bc_xprt = NULL;
	}

	svc_rdma_destroy_rw_ctxts(rdma);
	svc_rdma_send_ctxts_destroy(rdma);
	svc_rdma_recv_ctxts_destroy(rdma);

	/* Destroy the QP if present (not a listener) */
	if (rdma->sc_qp && !IS_ERR(rdma->sc_qp))
		ib_destroy_qp(rdma->sc_qp);

	if (rdma->sc_sq_cq && !IS_ERR(rdma->sc_sq_cq))
		ib_free_cq(rdma->sc_sq_cq);

	if (rdma->sc_rq_cq && !IS_ERR(rdma->sc_rq_cq))
		ib_free_cq(rdma->sc_rq_cq);

	if (rdma->sc_pd && !IS_ERR(rdma->sc_pd))
		ib_dealloc_pd(rdma->sc_pd);

	/* Destroy the CM ID */
	rdma_destroy_id(rdma->sc_cm_id);

	kfree(rdma);
}

static void svc_rdma_free(struct svc_xprt *xprt)
{
	struct svcxprt_rdma *rdma =
		container_of(xprt, struct svcxprt_rdma, sc_xprt);
	INIT_WORK(&rdma->sc_work, __svc_rdma_free);
	queue_work(svc_rdma_wq, &rdma->sc_work);
}

static int svc_rdma_has_wspace(struct svc_xprt *xprt)
{
	struct svcxprt_rdma *rdma =
		container_of(xprt, struct svcxprt_rdma, sc_xprt);

	/*
	 * If there are already waiters on the SQ,
	 * return false.
	 */
	if (waitqueue_active(&rdma->sc_send_wait))
		return 0;

	/* Otherwise return true. */
	return 1;
}

static void svc_rdma_secure_port(struct svc_rqst *rqstp)
{
	set_bit(RQ_SECURE, &rqstp->rq_flags);
}

static void svc_rdma_kill_temp_xprt(struct svc_xprt *xprt)
{
}